Flyingfish (Exocoetidae) species diversity and habitats in the eastern tropical Pacific Ocean.

Flyingfishes are large enough to eat zooplankton, small enough to be consumed by top predators, and therefore form a central mid-trophic component of tropical epipelagic marine food webs. Characterizing patterns of flyingfish abundance, distribution, and habitat preference have important implications for understanding both localized and generalized functions of marine ecosystems. The eastern tropical Pacific Ocean (ETP) supports many flyingfish species and their predators, yet no studies to date have identified oceanographic factors that define flyingfish habitats or estimate species richness and diversity at broad taxonomic and geographic scales. In this study, we analyzed 11,125 flyingfish representing 25 species and all 7 named genera, collected from the ETP over a 21-year period. We applied spatially-explicit analysis methods (ARCGIS, DIVA-GIS, MAXENT) and compared specimen locality data to remotely-sensed oceanographic data, and previously described oceanographic partitions. Our results show that Exocoetus is the most abundant genus (49%), and E. monocirrhus the most abundant species (32%) of flyingfishes in the ETP. Mean sea surface temperature was most important for defining flyingfish habitats (19.2-41.7%) and species richness (highest in the North Equatorial Current). Additionally, flyingfish species diversity was found to be highest in coastal regions of the study area (Shannon indices > 1.5). Together, these results provide unprecedented characterizations of a mid-trophic epipelagic community in an economically valuable region during a time when sea surface temperatures are predicted to increase as a result of global climate change.